A 3D Printed Linear Pneumatic Actuator for Position, Force and Impedance Control

Abstract

Although 3D printing has the potential to provide greater customization and to reduce the costs of creating actuators for industrial applications, the 3D printing of actuators is still a relatively new concept. We have developed a pneumatic actuator with 3D-printed parts and placed sensors for position and force control. So far, 3D printing has been used to create pneumatic actuators of the bellows type, thus having a limited travel distance, utilizing low pressures for actuation and being capable of only limited force production and response rates. In contrast, our actuator is linear with a large travel distance and operating at a relatively higher pressure, thus providing great forces and response rates, and this the main novelty of the work. We demonstrate solutions to key challenges that arise during the design and fabrication of 3D-printed linear actuators. These include: (1) the strategic use of metallic parts in high stress areas (i.e., the piston rod); (2) post-processing of the inner surface of the cylinder for smooth finish; (3) piston head design and seal placement for strong and leak-proof action; and (4) sensor choice and placement for position and force control. A permanent magnet placed in the piston head is detected using Hall effect sensors placed along the length of the cylinder to measure the position, and pressure sensors placed at the supply ports were used for force measurement. We demonstrate the actuator performing position, force and impedance control. Our work has the potential to open new avenues for creating less expensive, customizable and capable actuators for industrial and other applications.

A Miniature 3D Printed On-Off Linear Pneumatic Actuator and Its Demonstration into a Cartoon Character of a Hopping Lamp

“…It is currently limited to simple On-Off type applications. Ultimately, adding high bandwidth position and force control will expand the utility of such an actuator (e.g., [17]). In our experience, limitations of FDM based 3D printers such as low printer resolution, lack of isotropy of the finished parts, and poor quality control prevent the rapid prototyping of machines and mechanisms where high strength is desired.…”

Development of a 3D Printed Double-Acting Linear Pneumatic Actuator for the Tendon Gripping

“…Krause and Bhounsule [ 19 ] presented a linear pneumatic actuator fabricated using 3D printing technology with electronic sensors for force and position control. PolyLactic Acid (PLA) material was used for 3D printing.…”

“…Although 3D printing has been used to manufacture soft pneumatic actuators that operate at relatively low supply pressures, 3D printing has not been used to manufacture conventional pneumatic actuators, such as the piston-cylinder assembly, that can operate at standard pneumatic supply pressures. The fabrication of 3D printed actuators using plastic filaments and hobbyist printers poses a significant challenge, as the low resolution of hobbyist printers leads to the following problems: parts with limited strength, rough surfaces (high friction) that reduce efficiency, a considerable backlash that leads to leakage and anisotropy of parts that leads to directional strength [ 19 ].…”

A Piezoelectric and Electromagnetic Dual Mechanism Multimodal Linear Actuator for Generating Macro- and Nanomotion

“…In the fields of precision machines, intelligent manufacturing, robotics [1][2][3], and other active devices [4] for moving and driving an object precisely, actuators play an irreplaceable role. Conventionally, hydraulic pressure [5][6][7], pneumatic pressure [8,9], etc., can be transferred into mechanical motion. However, electric energy is more conveniently converted into motion and output force via electrostatic [6,10], piezoelectric, electroactive [11,12], electromagnetic induction, or magnetomotive force [13][14][15] coupling effects.…”